Compact managed pressure drilling system attached to rotating control device and method of maintaining pressure control

ABSTRACT

A managed Pressure Drilling manifold provides accurate back pressure control of a well head when drilling. The MPD system provides two paths for the drilling fluid to flow from the RCD to the flowline. The drilling fluid flows along an MPD path sending the drilling fluids through at least one sensor, preferably three sensors, a flow control device, and a flowmeter. The MPD system also provides a bypass path that isolates the flow control device and flowmeter while direct the drilling fluid from the RCD to the bypass to avoid the flow control device and flowmeter. The MPD system provides three valves that direct the drilling fluid in the bypass path or the MPD path.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and is a continuation of U.S. patentapplication Ser. No. 16/404,716 filed on May 6, 2019 entitled “COMPACTMANAGED PRESSURE DRILLING SYSTEM ATTACHED TO ROTATING CONTROL DEVICE ANDMETHOD OF MAINTAINING PRESSURE CONTROL” that is a continuation in partof U.S. patent application Ser. No. 15/097,270 filed on Apr. 12, 2016entitled “COMPACT MANAGED PRESSURE DRILLING SYSTEM ATTACHED TO ROTATINGCONTROL DEVICE AND METHOD OF MAINTAINING PRESSURE CONTROL” which is acontinuation in part of U.S. Patent Application No. 62/147,515 filed onApr. 14, 2015 entitled COMPACT MANAGED PRESSURE DRILLING SYSTEM ATTACHEDTO ROTATING CONTROL DEVICE AND METHOD OF MAINTAINING AUTOMATED SET POINTPRESSURE CONTROL and U.S. Patent Application No. 62/146,361 filed onApr. 12, 2015 entitled COMPACT MANAGED PRESSURE DRILLING MANIFOLD ANDMETHOD OF TUNING DRILLING PRESSURE CONTROL.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

Reference To A Microfiche Appendix

Not Applicable.

Reservation Of Rights

A portion of the disclosure of this patent document contains materialwhich is subject to intellectual property rights such as but not limitedto copyright, trademark, and/or trade dress protection. The owner has noobjection to the facsimile reproduction by anyone of the patent documentor the patent disclosure as it appears in the Patent and TrademarkOffice patent files or records but otherwise reserves all rightswhatsoever.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to managed pressure drilling (MPD)operations. More specifically, the present invention is related to acompact MPD manifold and a method of tuning pressure control. Thepresent invention is also related to a compact MPD system directlyattached to the RCD. The present invention is also related to a methodof maintaining automated set point pressure control with an automatedMPD system.

SUMMARY OF THE INVENTION

The present invention incorporates a rotating control device having twoor more major outlets incorporated into the RCD bowl/body. The primarymajor outlet is routed via a spool that incorporates three ports forPressure Transducers, such as sensors. The three transducers measure theupstream choke pressure. The redundancy of three pressure transducersenables 2 out of 3 voting of data validation for upstream chokepressure. A full bore fail last position actuated isolation valve islocated downstream from the spool. This validated pressure is used by acontrol system to accurately manipulate the choke/flow control device toaccurately control the well bore (Annular) pressure. The choke line thenis routed to inline flowmeter via manual isolation valve. The bypasslocated at rig flowline enables the system to bypass the MPD choke andmeter system.

The second major outlet routed via isolation valve routes to the rigsnormal drilling mud returns flowline. The present invention providesaccurate pressure control of the well bore with no rig modification toincorporate the MPD choke system. The present invention allows the choketo be isolated for non MPD conventional operations.

The present invention is a new compact low cost Managed PressureDrilling manifold that provides accurate back pressure control of a wellhead when drilling. The present invention provides a low cost MPDsolution to meet the needs of customers drilling unconventional wells inwhich the safety benefits of being able to apply surface back pressureare desirable but the cost associated with having a full conventionalMPD system is not economically viable.

The present invention provides a choke and may include a meteringsystem. The metering system includes a Coriolis meter or other flowmeterwith remote transmitter.

The present invention is designed to be as compact and as mobile aspossible to allow simple installation of sensitive equipment (PSU,controller & barriers). The control system (PSU, controller andbarriers) mounted in an Exd mobile enclosure. In one embodiment,connectors could be implemented to allow quick and fast connection ofpower, skid instruments, remote workstation and 3rd party data exchangevia communication link.

The pressure control system of the present invention utilizes anindependent back up (Pressure responsible Controller) to compare sensedpressure and send a control signal to a control element that maintainsthe process pressure at or near the set point value.

It is an object of the present invention to provide a compact manifolddesign.

It is also an object of the present invention to provide a moreresponsive manifold with quicker reaction time.

It is also an object of the present invention to provide desired flowcharacteristics.

It is also an object of the present invention to reduce the costs of theMPD system.

It is also an object of the present invention to reduce the weight ofthe MPD system.

It is an object of the present invention to provide a compact design.

It is also an object of the present invention to increase the safetybenefits.

It is also an object of the present invention to provide a low cost MPDsolution.

It is also an object of the present invention to maintain the processpressure at or near the set point value.

It is also an object of the present invention to validate pressure.

It is also an object of the present invention to have precise pressurecontrol without need for PID loop tuning.

It is also an object of the present invention to maintain automated setpoint pressure control.

It is also an object of the present invention to provide accuratepressure control.

It is also an object of the present invention to provide pressurecontrol without modifying the rig to incorporate an MPD system.

It is also an object of the present invention to isolate the choke fornon MPD conventional operations.

In addition to the features and advantages of the present invention,further advantages thereof will be apparent from the followingdescription in conjunction with the appended drawings.

These and other objects of the invention will become more fully apparentas the description proceeds in the following specification and theattached drawings. These and other objects and advantages of the presentinvention, along with features of novelty appurtenant thereto, willappear or become apparent in the course of the following descriptivesections.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following drawings, which form a part of the specification andwhich are to be construed in conjunction therewith, and in which likereference numerals have been employed throughout wherever possible toindicate like parts in the various views:

FIG. 1 is an environmental view of one embodiment of the presentinvention; and

FIG. 2 is a schematic view thereof.

DETAILED DESCRIPTION

The present invention is designed to be as compact and as mobile aspossible to allow simple installation of sensitive equipment (PSU,controller & barriers). The present invention provides a compact MPDsolution that provides a low cost MPD solution to meet the needs ofcustomers drilling unconventional wells in which the safety benefits ofbeing able to apply surface back pressure are desirable but the costassociated with having a full conventional MPD system is noteconomically viable.

The present invention incorporates a rotating control device 102 (“RCD”)having two major outlets 130, 132 incorporated into the RCD bowl/body.The primary major outlet 130 is routed via a spool 112 to the MPD path128 that incorporates three ports for Pressure Transducers, such assensors 116, 118, 120. The three transducers 116, 118, 120 measure theupstream choke pressure. The redundancy of three pressure transducers116, 118, 120 enables 2 out of 3 voting of data validation for upstreamchoke pressure. A full bore fail last position actuated isolation valve114 is located downstream from the spool 112. A control system uses thisvalidated pressure to accurately manipulate the flow control device 122,such as the choke, to accurately control the well bore (Annular)pressure. The choke line then is routed to inline flowmeter 110 viamanual isolation valve 108. Drilling fluid flowing through the flowcontrol device 122 and the flowmeter 110 flows along the MPD path 128.The bypass 107 located at rig flowline 124 enables the system to bypassthe MPD choke and meter system when flowing along the bypass path 126.

The second major outlet 132 routed via bypass valve 106 routes to therigs normal drilling mud returns flowline 124. The present inventionprovides accurate pressure control of the well bore with no rigmodification to incorporate the MPD choke system. The present inventionallows the flow control device 122 to be isolated for non MPDconventional operations.

The present invention is a new compact low cost Managed PressureDrilling system that provides accurate back pressure control of a wellhead when drilling. The present invention provides a low cost MPDsolution to meet the needs of customers drilling unconventional wells inwhich the safety benefits of being able to apply surface back pressureare desirable but the cost associated with having a full conventionalMPD system is not economically viable.

FIGS. 1-2 show a compact MPD system 100 directly attached to the flange104 of an RCD 102. The flanged connection at RCD 102 flange 104 supportsthe compact MPD system 100. The size and reduced weight of the compactMPD system 100 enables the MPD system 100 to be physically located onthe RCD 102.

In one embodiment, the MPD system 100 implements a flow control device122, such as rotary disc style choke. The flow control device 122 of oneembodiment operates via manipulator assembly and actuator, such as anelectrical actuator. The flow control device 122 controls the fluid flowthrough the flow control device 122.

A drip tray 98 that also functions as a work platform for users alsoattaches to the RCD 102. The RCD 102 flange 104 fits the flow controldevice, the isolation valve, and the bypass/integrated relief valve. Thereduced weight and size of the compact MPD system 100 is physicallylocated on the RCD 102.

FIGS. 1 and 2 show the MPD system 100 that is secured to the RCD 102 andthe flow of the drilling fluid from the RCD 102 to the rig flowline 124.The drilling fluid may flow through two different alternative paths toreach the flowline 124. The drilling fluid may flow through the MPD path128 or through the bypass path 126. The drilling fluid may flow throughthe flow control device 122 and the flowmeter 110 to the flowline 124 byclosing the bypass valve 106 and opening valves 108, 114. Closing bypassvalve 106 and opening valves 108, 114 directs the drilling fluid throughthe MPD path 128 to the flowline 124. Alternatively, opening the bypassvalve 106 and closing the valves 108, 114 directs the drilling fluidthrough the bypass path 126 and the bypass 107 to the flowline 124.

Closing bypass valve 106 directs the drilling fluid through the MPD path128 through the flow control device 122 and the flowmeter 110. Openingvalves 108, 114 while bypass valve 106 is closed provides the MPD path128 for the drilling fluid to flow through the flow control device 122and flowmeter 110 to the flowline 124. The drilling fluid flows past thepressure transducers 116, 118, 120. The pressure transducers 116, 118,120 check upstream choke pressure. The multiple transducers 116, 118,120 validate pressure to accurately manipulate the flow control device122. The drilling fluid flows through the valve 114 and the flow controldevice 122 to the flowmeter 110. The drilling fluid then flows throughthe valve 108 to the flowline 124.

Closing valves 108, 114 and opening bypass valve 106 directs thedrilling fluid through the bypass 107 to the flowline 124. Closingvalves 108, 114 isolates the MPD system 100 and directs the drillingfluid through the bypass 107 along the bypass path 126.

FIG. 2 provides more information regarding the compact MPD system 100and the flow of the drilling fluid. The MPD system 100 attaches at theflange 104 of RCD 102. Flow control device 122 controls the flow of thedrilling fluid through the compact MPD system 100. Such flow controldevices may include, but are not limited to chokes, valves, rotary VeeBalls, and Rotary Disc style Chokes.

FIG. 2 shows the MPD system 100 with pressure sensors 116, 118, 120. Theincreased number of pressure sensors 116, 118, 120 provides the MPDsystem 100 with additional information. Such additional sensors 116,118, 120 enable automated control and alarms.

FIG. 2 shows the two different flow paths from the RCD 102 to theflowline. The drilling fluid flows through the MPD path 128 or throughthe bypass path 126. Valves 106, 108, 114 control the path through whichthe drilling fluid will flow.

The drilling fluid flows past the transducers 116, 118, 120 secured tothe spool 112 attached to the flange 104. The transducers 116, 118, 120directly attach to the flange 104 via spool 112. The drilling fluid whenflowing through the MPD system flows past the transducers 116, 118, 120through the valve 114 past the flow control device 122 and flowmeter 110through valve 108 to the flowline 124. Bypass valve 106 is closed whilevalves 108, 114 remain open to direct the drilling fluid through theflow control device 122 and the flow meter 110 along the MPD path 128.

The valves 106, 108, 114 also isolate the MPD system 100. Opening bypassvalve 106 and closing valves 108, 114 isolates the MPD system 100 anddirects the drilling fluid through bypass 107 to the flowline 124 alongthe bypass path 126.

1.1 Pressure Transmitter

In one embodiment, at least one Pressure Transmitter determines theupstream pressure on the choke manifold. Other embodiments may includemultiple Pressure Transmitters. The Pressure Transmitter also providesfor the primary process measurement for back pressure control. Note thisPressure Transmitter is located upstream of the isolation valve directlyon the RCD.

1.2 Flow Transmitter

A Coriolis meter may be used for measuring mass flow and density. Meterdiagnostics shall also be required in one embodiment for advancecondition monitoring of the process such as gas breakout or presenceetc. The unit shall include a remote transmitter head installed forextra protection during mobilization and normal operations. The flowtransmitter is capable of determining the condition of the meter tubesand is capable of real time health of meter monitoring. The offset drivefunction will be used as an indicator to the presence of gas in thereturn flow.

1.3 Isolation Valves

The choke manifold of one embodiment is designed with two flow paths.Each flow path is protected by an actuated isolating valve.

1.4 Pressure Control

The flow control device 122 is installed on the well head main flowline. Well head pressure is controlled using modulating the flow controldevice in the flow line. Effects of gas in the Coriolis meter:

The Coriolis meter used in the manifold of the present invention is notadversely affected by gas break out in the Coriolis tubes. The Coriolismeter recognizes the presence of gas by a change in the offset driveparameters. It is important to determine if the timing of changes in theoffset drive parameters can be calculated to determine if theycorrespond to particular events such as Bottom up time from a drillingconnection or a known positive drilling break.

1. Intelligent Sensors/Real Time Health Monitoring:

One of the key differences between the present invention and the knownart is that the present invention continuously monitors its own healthand the condition of its key equipment components. In doing so, thesystem of the present invention can alert the user to both ongoingproblems such as equipment blockage/plugging events or general wear andtear/decrease in operability through usage.

EXAMPLES

Flow Control Valve wear: When the control valves are newly installed,the control system takes a signature of response of the valve to controlseveral pressure set points at several given flow rates. This signatureis then used as a reference point to the performance of the valvesoperating performance throughout its operational life. This means thatthe system can identify if a valve is requiring a greater degree ofclosure on a control valve than should be required and can then alertthe MPD technician that the control valve is suffering fromwear/erosion.

Increased Torque to operate valve: Again the system can alert the MPDtechnician of increased torque values to operate valves alerting theoperator to inspect, clean and grease valves stems etc.

Coriolis Tube Monitoring: The condition of the pressure containingCoriolis meter tubes is a critical parameter to monitor

This real time equipment health monitoring will may be utilized forpreventative equipment maintenance.

In one embodiment, the system of the present invention may bepredominantly operated by either the client or the drilling contractor.In another embodiment, the system of the present invention may beremotely supported, updated, and operated by personnel from a remotecontrol center. In such a situation of remote operating, real timehealth monitoring capabilities of the system will be of vital importancein order for remote personnel to continue to deliver effective wellcontrolled operations.

From the foregoing, it will be seen that the present invention is onewell adapted to obtain all the ends and objects herein set forth,together with other advantages which are inherent to the structure.

It will be understood that certain features and subcombinations are ofutility and may be employed without reference to other features andsubcombinations. This is contemplated by and is within the scope of theclaims.

As many possible embodiments may be made of the invention withoutdeparting from the scope thereof, it is to be understood that all matterherein set forth or shown in the accompanying drawings is to beinterpreted as illustrative and not in a limiting sense.

What is claimed is:
 1. A managed pressure drilling (MPD) system for useon a rotating control device (RCD) having a first outlet and a secondoutlet at a well, the MPD system connected to a flange at the firstoutlet of the RCD, wherein drilling fluid flows downstream from the RCDto a flowline, the MPD system comprising: a first sensor detecting apressure within the flowline; a flow control device attached to the RCDwherein the first sensor detects the pressure upstream of the flowcontrol device between the RCD and the flow control device; and an MPDpath directing the drilling fluid through the flow control device to theflowline, wherein the drilling fluid flows from the first outlet throughthe MPD path, wherein the first sensor detects the pressure in the MPDpath upstream of the flow control device between the first outlet andthe flow control device; and a bypass valve connected to the secondoutlet of the RCD wherein the bypass valve is located upstream of theflowline.
 2. The system of claim 1 further comprising: a flow meterlocated downstream of the flow control device; a second valve locateddownstream of the flowmeter, wherein the second valve is locatedupstream of the flowline, wherein the drilling fluid flows through thesecond valve to the flowline; wherein the drilling fluid flows throughthe bypass valve into the flowline.
 3. The system of claim 2 whereinclosing the first valve and the second valve and opening the bypassvalve directs the drilling fluid from the RCD through a bypass thatavoids the flowmeter and the flow control device to the flowline.
 4. Thesystem of claim 3 wherein opening the first valve and the second valveand closing the bypass valve directs the drilling fluid from the RCDthrough the first sensor, the flow control device, and the flowmeter tothe flowline.
 5. The system of claim 1 further comprising: a first valvelocated downstream of the first sensor.
 6. The system of claim 5 whereinthe first valve is located upstream of the flow control device, thefirst valve located between the flow control device and the firstsensor.
 7. The system of claim 5 further comprising: a flow meterlocated downstream of the flow control device.
 8. The system of claim 7further comprising: a second valve located downstream of the flowmeter,wherein the second valve is located upstream of the flowline, whereinthe drilling fluid flows through the second valve to the flowline.
 9. Amanaged pressure drilling (MPD) system for use on a rotating controldevice (RCD) having a first outlet and a second outlet at a well whereinthe MPD system is located downstream of a first outlet of the RCD, theMPD connected to a flange at the first outlet of the RCD, whereindrilling fluid flows downstream from the RCD to a flowline, the MPDsystem comprising: a flow control device connected to the RCD, the flowcontrol device located within an MPD path; the MPD path directing thedrilling fluid through the flow control device to the flowline, whereinthe drilling fluid flows from the first outlet through the MPD path; apressure transducer detecting pressure of the drilling fluid within theMPD path upstream of the flow control device; and a bypass locatedupstream of the flow control device for fluid to bypass the flow controldevice.
 10. The MPD system of claim 9 further comprising: a drip traysecured to the RCD wherein the drip tray catches mud from the RCD. 11.The MPD system of claim 10 wherein the drip tray extends outward fromthe RCD to extend underneath the flow control device of the MPD system.12. The MPD system of claim 11 further comprising: at least one outletfrom the drip tray, the outlet attaching to a conduit for transferringmud from the drip tray to storage.
 13. A managed pressure drilling (MPD)system for use on a rotating control device (RCD) having a first outletand a second outlet at a well, wherein drilling fluid flows downstreamfrom the RCD to a flowline, the system comprising: a first pressuretransducer detecting a pressure of the drilling fluid; a flow controldevice connected to the RCD, the flow control device located within anMPD path, wherein the first pressure transducer detects the pressureupstream of the flow control device between the first outlet and theflow control device; an MPD path directing the drilling fluid throughthe flow control device and to the flowline, wherein the drilling fluidflows from the first outlet through the MPD path; a bypass pathdirecting the drilling fluid to the flowline avoiding the flow controldevice, wherein the drilling fluid flows from the second outlet throughthe bypass path.
 14. The system of claim 13 further comprising: a firstvalve located downstream of the first pressure transducer, wherein thefirst valve is located upstream of the flow control device, the firstvalve located between the flow control device and the first pressuretransducer.
 15. The system of claim 14 further comprising: a flow meterlocated downstream of the flow control device.
 16. The system of claim15 further comprising: a second valve located downstream of theflowmeter, wherein the second valve is located upstream of the flowline,wherein the drilling fluid flows through the second valve to theflowline.
 17. The system of claim 16 further comprising: a bypass valveconnected to the second outlet of the RCD wherein the bypass valve islocated upstream of the flowline, wherein the drilling fluid flowsthrough the bypass valve into the flowline.
 18. The system of claim 17wherein closing the first valve and the second valve and opening thebypass valve directs the drilling fluid from the RCD through the bypasspath through a bypass to the flowline avoiding the flow control deviceand the flowmeter.
 19. The system of claim 17 wherein opening the firstvalve and the second valve and closing the bypass valve directs thedrilling fluid from the RCD through the MPD path through the firstpressure transducer, the flow control device, and the flowmeter to theflowline through the MPD path.